fix(core): timezone offset issue in util

[AidanHost]

Description

Correcting the timezone offset and timestamp conversion calculation

Related issues

Follows on from #4055

Release Summary

Checklist

• I read the Contributor Guide and followed the process outlined there for submitting PRs.
  • Yes
• My change supports the following platforms;
  • Android
  • iOS
• My change includes tests;
  • e2e tests added or updated in packages/\*\*/e2e
  • jest tests added or updated in packages/\*\*/__tests__
• I have updated TypeScript types that are affected by my change.
• This is a breaking change;
  • Yes
  • No

Test Plan

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[CLAassistant]

All committers have signed the CLA.

[Salakar]

LGTM, thanks

[AidanHost]

I see we're not the only team that gets E2E timeouts 😄 . I don't see a way to re-run the checks, maybe only write permissions on the repo can re-run?

[mikehardy]

detox[4758] INFO:  [DetoxServer.js] server listening on localhost:49713...
detox[4758] ERROR: [exec.js/EXEC_FAIL, #23] ""/Users/runner/Library/Android/sdk/platform-tools/adb" -s emulator-5554 shell "ps | grep \"com\.invertase\.testing$\""" failed with code = 1, stdout and stderr:

detox[4758] ERROR: [exec.js/EXEC_FAIL, #23] 
detox[4758] ERROR: [exec.js/EXEC_FAIL, #23] 
  1) "before all" hook in "{root}"
detox[4758] INFO:  at e2e/init.js:53:11 
  ✨ Tests Complete ✨ 
detox[4758] ERROR: at internal/process/warning.js:25:20 
 (node:4758) UnhandledPromiseRejectionWarning: DetoxRuntimeError: Failed to run application on the device

Not enough to go on why, but it's somewhere in initial detox+app hookup, either APK install (Salakar theory) or something else unknown (my theory), with no data (yet) to validate either theory :)

I hit the re-run job button, 🤞

[mikehardy]

Hopefully that one does the trick, thanks again @AidanHost